Two cases of Hutchinson-Gilford progeria syndrome are presented with a focus on hip disease. A severe coxa valga is the first abnormality. The femoral head becomes increasingly uncovered as the acetabulum becomes more dysplastic. The center edge angle decreases, the acetabular index increases, and the medial wall of the acetabulum widens. Hip pain, subluxation, and eventually dislocation are the sequelae of these changes. Late osteotomy is unpredictable; thus the best therapeutic regimen is early osteotomy (age 4-6 years) and a regular exercise program to maintain muscle strength and range of motion.